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The effect of SiO2 additions, from 0.2% to 10% in weight, on the magnetic and structural properties of barium ferrite, prepared by the chemical coprecipitation method, is reported. It was observed that the effect of silicon oxide on the ferrite is to drag the grain growth and to decompose the ferrite into hematite and, perhaps, a barium silicate.Se estudia el efecto de la influencia que tiene la adición de SiO2, en cantidades del 0.2% al 10% en peso, sobre las propiedades magnéticas y estructurales de las ferritas de bario preparadas por el método de coprecipitación química. Se observó que el efecto del óxido de silicio sobre la ferrita de bario fue el de actuar como inhibidor para el crecimiento del grano y el de descomponer la ferrita en hematita y, posiblemente, en un silicato de bario.

Presents a study which reported measurements of the alternating current (ac) magnetic susceptibility on gadolinium thin films grown in ultrahigh vacuum. Experimental details; Method used in measuring in situ the ac magnetic susceptibility in thin films; Results of the ac magnetic susceptibility of the film.

The magnetocaloric properties and the magnetic phase transition of the rare earth manganites LaCaSrMnO ( x = 0.05, 0.06, 0.07, 0.08) have been studied. Three methods were used to determine the order of the magnetic transition: isothermal magnetization curves; magnetization as a function of the temperature; and the phenomenological, universal curve. And it was found to be a second-order transition. [ABSTRACT FROM AUTHOR]

Pure lead hexaferrite (PbFe12O19) was obtained using two different methods of preparation, the solid state reaction and the chemical coprecipitation. It was found that the lead hexaferrite prepared by the solid state method is obtained without secondary phases by adding 33.09 % of lead oxide as an excess and sintering at 950 °C during one hour, also the pure lead hexaferrite prepared by the coprecipitation method is obtained at 700 °C without lead losses. We studied the structural and magnetic properties of both samples, a remarkable increase was found in the coercivity field of the sample prepared by coprecipitation as well as a reduction of the magnetic saturation, compared with the sample prepared by the solid state reaction. This behavior is attributed to the morphologic characteristics and the microstructure that is obtained in an inherently way to the preparation method. [ABSTRACT FROM AUTHOR]

In this work, we present a systematic study on the magnetic properties of Nd3+-susbtituted SrM hexaferrites following the formula SrNdxFe12-xO19, (x = 0.0 - 0.5). The microstructure characterization indicates the formation of a solid solution for Nd contents at x = 0.1, while a composite Sr(NdFe)12O19/SrFeO3 distribution of phases results for x > 0.1. Interesting combination of hard magnetic properties were obtained for the whole compositional series, such as increasing coercivity values of up to 329 kA/m for x = 0.5 with increasing Nd concentration. Results are interpreted in terms intrinsic property variations. [ABSTRACT FROM AUTHOR]

Here we present two cases of entomophthoramycosis in young children, these were the first cases ever diagnosed at our center. Both cases represented a diagnostic and treatment challenge. Surgical treatment was key in the management of both patients. Even though atypical disease was encountered, clinical response was obtained after surgical excision and antifungal treatment for a few months., Competing Interests: Please declare any financial or personal interests that might be potentially viewed to influence the work presented. Interests could include consultancies, honoraria, patent ownership or other. If there are none state ‘there are none.’, (© 2022 Published by Elsevier B.V. on behalf of International Society for Human and Animal Mycology.)

A case of endobronchitis by Scedosporium apiospermum in a child with cystic fibrosis is presented. The bronchial aspirate's cytology showed the presence of a large amount of septated-dichotomized hyphae. The bronchial aspirate's culture showed the presence of Scedosporium apiospermum in a pure culture of three consecutive samples. The scanning electron microscopy study of the mucosal surface revealed scarce mycelia with the presence of abundant conidiae. The transmission electron microscopy of the mucosa revealed inflammatory infiltrates constituted by macrophages, polymorphonuclear leukocytes, a lot of dichotomized mycelia and macrophages with hyphae and conidiae within the phagosomes. The patient was treated with amphotericin B and itraconazole.